For the emergent reversal of anticoagulation, there is only one dose and one route of vitamin K that should be used: 10 mg of IV vitamin K infused over 30 minutes. Regardless of the reason for anticoagulation, major haemorrhage in a patient on the anticoagulant warfarin is best managed by rapid and complete reversal with a prothrombin complex concentrate and intravenous (IV) vitamin K Clinical predictors of prolonged delay in return of the international normalized ratio to within the therapeutic range after excessive anticoagulation with warfarin. Reversal of warfarin with Vitamin K should be reserved only for the most serious bleeding events or patients who will not be restarted on warfarin. Vitamin K should be administered either orally or intravenously (IV) only. Oral Vitamin K is the safest and most reliable route. Timely and effective pharmacologic reversal of anticoagulation remains critical for events of major bleeding, emergency surgery, and high-risk procedures. Vitamin K and prothrombin complex concentrate (PCCs) can be used for warfarin reversal. Andexanet alfa and idarucizumab are specific reversal agents for DOACs and DTIs, respectively. Sign up today to receive the latest news and updates from UpToDate. © 2026 UpToDate, Inc. and/or its affiliates. All Rights Reserved. Whenever possible, anticoagulation should be resumed in a timely manner to avoid thromboembolic complications related to the underlying indication for anticoagulation. Conversion to warfarin: Since dabigatran contributes to INR elevation, warfarin’s effect on the INR will be better reflected only after dabigatran has been stopped for ≥2 days. Evidence-based management of anticoagulant therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012 Feb;141 PDF.